Search results
Results from the WOW.Com Content Network
Influenza, commonly known as the flu, is an infectious disease caused by influenza viruses.Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue.
Influenza A viruses are further classified, based on the viral surface proteins hemagglutinin (HA or H) and neuraminidase (NA or N). 18 HA subtypes (or serotypes) and 11 NA subtypes of influenza A virus have been isolated in nature. Among these, the HA subtype 1-16 and NA subtype 1-9 are found in wild waterfowl and shorebirds and the HA ...
The bacteria are mesophilic and grow best at temperatures between 35 and 37 °C. [1] H. influenzae was first described in 1893 [2] [3] by Richard Pfeiffer during an influenza pandemic [4] when he incorrectly identified it as the causative microbe, which is why the bacteria was given the name "influenzae".
Influenza A virus (IAV) is the only species of the genus Alphainfluenzavirus of the virus family Orthomyxoviridae. [1] It is a pathogen with strains that infect birds and some mammals, as well as causing seasonal flu in humans. [2]
Transmission electron microscope image of a recreated 1918 influenza virus. A pandemic is a worldwide epidemic. The 1918 flu pandemic, which lasted until 1919, was a category 5 influenza pandemic caused by an unusually severe and deadly influenza A virus. The victims were often healthy young adults, in contrast to most influenza outbreaks ...
The ancestor of influenza viruses A and B and the ancestor of influenza virus C are estimated to have diverged from a common ancestor around 8,000 years ago. Influenza viruses A and B are estimated to have diverged from a single ancestor around 4,000 years ago, while the subtypes of influenza A virus are estimated to have diverged 2,000 years ...
Cap snatching is best described in influenza viruses, especially influenza A. In Orthomyxoviridae , the viral family of influenza, the RdRp is divided into three subunits: PA, PB1 and PB2. PB1 first binds the 5’ end of the viral RNA (vRNA), activating PB2 and causing the 3’ end of the vRNA to form a double-stranded zone with the 5’ end.
Swine influenza (also known as swine flu or pig flu) is a respiratory disease that occurs in pigs that is caused by the Influenza A virus. Influenza viruses that are normally found in swine are known as swine influenza viruses (SIVs). The three main subtypes of SIV that circulate globally are A(H1N1), A(H1N2), and A(H3N2).